Some people use a rope or such to tie it up...some drill a hole through the core of it to put the rope through. That seems too hard for me...lol.

What I do is use one of those nylon fish stringers & poke the pointy metal thing through the core of the cabbage. Sometimes I have to bang it a little on something hard to get it to go all the way in. I leave it tied up out there & pull the rope & pointy thing up out of the way when there's no head of cabbage on it so that it's not just dangling down empty.

You can kinda file down the pointy metal thing to dull it some if you're worried they'll get poked with it. I did that on one of the cheaper short ones, but now I have one where the rope is a lot longer & stronger & the pointy metal thing is already pretty dull & a lot more sturdy than the cheap one.

I recently bought a head of cabbage to divide up between the flocks. I have very picky chickens and I didn't want to waste money on something they weren't going to eat.....they went NUTS. It was ALL gone in a matter of minutes!!! I just cut it in half and dropped it on the ground. They had a ball!